大豆豆荚光合物质转运与分配对籽粒发育的影响

运用透射电镜放射自显影技术、液体闪烁计数仪和相关生理指标测定研究了大豆生长过程中不同时期豆荚光合产物对籽粒发育的影响。结果如下:在鼓粒初期、鼓粒中期、鼓粒后期豆荚都向籽粒转运光合产物;豆荚和叶片在鼓粒中期14C-同化物的转运量达到最大;叶绿素、可溶性碳水化合物的含量也达到最高。鼓粒中期豆荚的转运量可达叶片转运量的35.6%;鼓粒后期豆荚、叶片的转运量都有所下降,但叶片下降幅度大于豆荚,此时期豆荚对籽粒的转运量达到叶片的59.6%。可见在鼓粒后期,当叶片光合功能开始衰退时,豆荚的光合产物对籽粒的贡献起到不容忽视的作用。

EFFECTS OF PHOTOSYNTHATE TRANSPORTATION AND DISTRIBUTION IN SOYBEAN PODS ON THE DEVELOPMENT OF SOYBEAN SEEDS

Photosynthate for seeds development in soybean pods at different pod-filling stage was studied by electron microscope autoradiography,liquid scintillation counter and physiological indexes measuring.The results showed that the transportation of photosynthate from pods and leaves to seeds was throughout all pod-filling stages,while the transportation of( ~(14)C-) labeled photo-assimilates was largest from pods and leaves in middle pod-filling period,and the content of chlorophyll and carbohydrate were also the largest from pods in middle pod-filling period.The transportation of ~(14)C-labeled photo-assimilates from pods was about 35.6% of that from leaves.At later pod-filing period the transportation of ~(14)C-labeled photo-assimilates from pods and leaves decreased,but the decline rate was bigger from leaves than from pods and the transportation of ~(14)C-labeled photo-assimilates from pods was taking about 59.6% of that from leaves.It indicated that the seeds assimilates were compensated by soybean pods′ photosynthate when their leaves photosynthetic capacity decreased at later pod-filling period.